1. Field of the Invention
The present invention relates to apparatuses for connecting body components such as tubular members.
2. Description of the Prior Art
Connections between pipe sections, a pipe section and a valve, or between any two bodies having tubular portions that are connectable to provide a fluid flow passage are commonly made using flange assemblies. One type of flange assembly, commonly referred to as a swivel flange assembly, has two subassemblies, each having a flange or collar that is rotatable and axially movable relative to a hub or nipple. In these swivel flange assemblies, the hub or nipple is provided with a radially outwardly facing, annularly extending groove into which are received split ring segments. The split rings project radially outwardly from the groove in the hub or nipple and provide a right-angled shoulder against which one flange is urged as it is bolted to the adjoining flange. This shoulder supports the loads imposed by the bolts holding the flange assemblies together. While other prior art swivel-type flange assemblies have tapered hubs and flanges, for all intents and purposes the taper angle is so large, e.g., 65xc2x0, that they behave essentially like a right-angled shoulder. Because of this type of shouldering, high stress concentrations are created at the juncture of the shoulder(s) and the hub(s) or nipple(s).
In flange assemblies, both of the standard and swivel type, metal seal rings have been utilized to obtain metal-to-metal sealing between the two flange subassemblies. Typically, this has necessitated that a metal seal ring, or at least a portion thereof, be compressed between the hub faces by the nut and bolt assemblies used to clamp the flange subassemblies together. However, in these types of prior art flange assemblies, there typically is not metal-to-metal sealing between the hub faces themselves as opposed to being between the hub faces and the seal ring or a portion thereof compressed therebetween.
It is therefore an object of the present invention to provide an apparatus for connecting tubular bodies.
A further object of the present invention is to provide an apparatus for connecting tubular bodies in fluid-tight engagement with one another, which provides a metal-to-metal seal.
Still a further object of the present invention is to provide an apparatus for connecting tubular bodies together that can withstand high bending moments.
Yet a further object of the present invention is to provide an apparatus for connecting tubular bodies together that provides separate metal-to-metal seals.
The above and other objects of the present invention will become apparent from the drawings, the description given herein, and the appended claims.
In one embodiment, the apparatus of the present invention includes a first flange assembly that comprises a first hub defining a first flow path and having a first, substantially annularly extending, radially outwardly facing frustoconical hub surface, a first annularly extending, axially facing hub seal face, and a first connection end for connecting to a first tubular body. The first frustoconical hub surface has its greatest diameter more proximate the first hub seal face than the first connection end. The first flange assembly further includes a first annular flange in surrounding relationship to the first hub and having a first axial end, a second axial end, and a first annularly extending, radially inwardly facing frustoconical flange surface, the first frustoconical flange surface and the first frustoconical hub surface being complementary to one another. The first frustoconical flange surface extends substantially from the first end to the second end of the first annular flange. The second flange assembly of the present invention includes a second hub defining a second flow path and having a second, substantially annularly extending, radially outwardly facing frustoconical hub surface, a second annularly extending, axially facing hub seal face, and a second connection end for connecting to a second tubular body. The second frustoconical hub surface has its greatest diameter more proximate the first hub seal face than the second connection end. The second flange assembly further includes a second annular flange in surrounding relationship to the second hub and having a first axial end, a second axial end, and a second, annularly extending, radially inwardly facing frustoconical flange surface that is complementary to the second frustoconical hub surface. The second frustoconical flange surface extends substantially from the first axial end to the second axial end of the second annular flange. A compression assembly, e.g., nuts and bolts, operatively connected to the first and second flange members, urges the first and second flange assemblies toward one another.
In another embodiment of the present invention, there is provided an apparatus for connecting first and second tubular bodies together comprising a first flange assembly and a second flange assembly. The first flange assembly has a first hub that defines a first flow path and a first substantially annularly extending, radially outwardly facing frustoconical hub surface and a first, annularly extending, axially facing hub seal face. The first hub further has a first connection end for connecting to a first tubular body, the first frustoconical hub surface having its greatest diameter more proximate the first hub seal face than the first connection end. The first flange assembly further includes a first annular flange in surrounding relationship to the first hub, the first flange having a first annularly extending, radially inwardly facing frustoconical flange surface that is complementary to the first frustoconical hub surface. The second flange assembly includes a second hub defining a second flow path and having a second, substantially annularly extending, radially outwardly facing frustoconical hub surface and a second, annularly extending, axially facing hub seal face. The second hub further has a second connection end for connecting to a second tubular body, the second frustoconical hub surface having its greatest diameter more proximate the first hub seal face than the second connection end. The second flange assembly further includes a second annular flange in surrounding relationship to the second hub, the second flange having a second annularly extending, radially inwardly facing, frustoconical flange surface that is complementary to the second frustoconical hub surface. A compression assembly, operatively connected to the first and second flange members, urges the first and second flange assemblies toward one another and the first and second hub seal faces into metal-to-metal sealing engagement. The angle between an axis coaxial with the first and second flow path when the first and second hub seal faces are in metal-to-metal sealing engagement and an imaginary line passing through either of the frustoconical surfaces on the first and second hubs is from 10xc2x0 to 30xc2x0.
In still a further embodiment of the present invention, there is provided an apparatus for connecting first and second tubular bodies together that comprises first and second flange assemblies. The first flange assembly has a first hub defining a first flow path and having a first, annularly extending, axially facing hub seal and a first annular flange in surrounding relationship to the first hub. The second flange assembly comprises a second hub defining a second flow path having a second, annularly extending, axially facing hub seal face and a second annular flange in surrounding relationship to the second hub. The compression assembly, operatively connected to the first and second flange members, urges the first and second flange assemblies toward one another. There is a first interconnection between the first hub and the first flange and a second interconnection between the second hub and the second flange whereby when the compression assembly urges the first and second flange assemblies together, the first and second hub seal faces are urged into metal-to-metal sealing engagement. The first hub seal face and the second hub seal face have first and second annular registering seal ring grooves, respectively, each of the first and second seal ring grooves having an annular, radially innermost wall, an annular, radially outermost wall, and an axially facing end wall connecting the radially innermost and radially outermost walls, the radially outermost walls having radially inwardly facing, annularly extending frustoconical groove surfaces, the frustoconical groove surfaces having their greatest diameter more proximate the hub seal faces than the end walls. An annular metallic seal ring has a first portion received in the first seal ring groove and a second portion received in the second seal ring groove. The first portion of the seal ring groove has a first, radially outwardly facing, annularly extending frustoconical seal ring surface complementary to the frustoconical surface in the first seal ring groove, and the second portion of the seal ring has a second, radially outwardly facing, annularly extending frustoconical seal ring surface complementary to the frustoconical groove surface in the second groove. The seal ring also has a second radially inwardly facing, annularly extending seal ring surface and opposed, axially facing end surfaces. The frustoconical surfaces on the seal ring are dimensioned relative to the frustoconical surfaces in the groove such that, prior to metal-to-metal engagement or sealing between the first and second hub seal faces, there is interference engagement between all of the frustoconical surface on the first portion of the seal ring with at least a portion of the frustoconical surface in the first groove and all of the frustoconical surface on the second portion of the seal ring with at least a portion of the frustoconical surface in the second seal ring groove. Additionally, the seal ring is dimensioned relative to the registering seal ring grooves such that the axially facing end surfaces of the seal ring are spaced from the axially facing end walls and the second seal ring surface is radially spaced from the radially innermost walls of the seal ring grooves when the hub seal faces are in metal-to-metal, preferably sealing, engagement. The angle between an axis coaxial with the first and second flow paths when the hub seal faces are in metal-to-metal engagement and an imaginary line passing through either of the frustoconical surfaces on the seal ring is from 5xc2x0 to 25xc2x0.
In yet another embodiment of the present invention, there is provided an apparatus for connecting first and second tubular bodies together, as described just immediately above, but wherein the seal in the first and second seal ring grooves is made up of a first seal ring segment received in the first seal ring groove and a second seal ring segment received in the second seal ring groove. The first seal ring segment has a first axially facing seal ring face; a first, opposed axially facing end surface; a first, radially outwardly facing, annularly extending frustoconical seal ring segment surface complementary to the frustoconical groove surface in the first seal ring groove; and a first, annularly extending, radially inwardly facing seal ring segment surface. The second seal ring segment has a second axially facing seal ring face; a second, opposed axially facing end surface; a second, radially outwardly facing, annularly extending frustoconical seal ring segment surface complementary to the frustoconical groove surface in the second seal ring groove; and a second, annularly extending, radially inwardly facing seal ring segment surface. The first frustoconical seal ring segment surface is dimensioned relative to the first frustoconical surface in the first seal ring groove, and the second frustoconical seal ring segment surface is dimensioned relative to the frustoconical surface in the second seal ring groove such that there is interference engagement between substantially all of the first frustoconical seal ring segment surface and at least a portion of the first frustoconical surface in the first seal ring groove, and between substantially all of the second frustoconical seal ring segment surface and at least a portion of the frustoconical surface in the second seal ring groove prior to metal-to-metal engagement or sealing between the first and second hub seal faces. The first and second seal ring faces on the first and second seal ring segments are in metal-to-metal sealing engagement when the first and second hub seal faces are in metal-to-metal engagement. The seal ring segments are also dimensioned relative to the seal ring grooves such that the first end surface is spaced from the axially facing end wall of the first groove, the second end surface is spaced from the axially facing end wall of the second groove, and the first and second radially inwardly facing seal ring segment surfaces are spaced from the first and second radially innermost walls in the first and second grooves, respectively, when the first and second hub seal faces are in metal-to-metal, preferably sealing, engagement. The angle of the frustoconical surfaces on the seal ring segments is as described above with respect to the single seal ring.